The trailer socket tester switch allows for quick detection of issues related to malfunction and defective trailer indicator lights. When the test button is pressed, the switch analyzes the 6 positions of the diagnostic socket. Lighting issues are detected quickly and easily. Ideal for trailer owners, trailer rental locations, car workshops, electricians, and more. The switch is powered by a 9V battery (not included).

Professional Diagnosis

• Red light – parking signal
• Yellow light – left indicator
• Blue light – rear fog lights or 12V
• Black light – left rear light
• White light – ground
• Green light – right indicator
• Brown light – right rear light

How to perform a socket or plug test

• Connect the switch to the socket of the towing vehicle – the lights are red.
• Turn on a specific light (such as the parking light), the indicator turns green.
• If the indicator is red, it means the installation is defective.

How to perform a trailer installation test

• Connect the plug to the switch.
• Press the yellow button on the switch.
• Green light means the installation works.
• Red light means the installation is defective or the bulb is burned out.

Includes:

• Socket tester switch
• 13/7 adapter
• 7/13 adapter